Gas to oil convertors have been proposed for various industrial equipment in geographic areas where industrial gas is in scarce supply and/or unduly expensive. The present invention is particularly concerned with food processing ovens where the food, such as bakery products, is subject to contamination by the products of incomplete combustion and considerable care must be exercised in burning the fuel. Another factor is the absolute necessity to maintain the oven chamber free of unburned fuel which might cause explosions.
One of the prime objects of the present invention is to provide a direct fired food processing oven wherein bread, buns, and various other bakery products may be safely baked with oil or gas as a fuel, as energy conservation needs dictate, so that baking need not be curtailed in times when gas is in short supply.
Another object of the invention is to provide a system of the character described which maintains the oven chamber free of combustible volatiles which could accumulate and cause explosions.
Still another object of the invention is to provide a system in which the burner assemblies are preheated to a predesignated temperature before any fuel can be burned, and wherein the oven must first burn gas and can only burn oil when a predetermined temperature is reached within the oven chamber.
Still another object of the invention is to provide a system of this character wherein, if the oven chamber temperature falls below a predetermined temperature, the system immediately automatically ceases to burn oil and can only recommence to burn oil after burning gas for a time to raise the oven chamber temperature once again to the predetermined level.
Still another object of the invention is to provide a system incorporating all of these advantages, which has multiple chamber zones with a bank of burners in each operable individually and selectively to burn gas and oil in the manner indicated.
Other objects and advantages of the invention will be pointed out specifically or will become apparent from the following description when it is considered in conjunction with the appended claims and the accompanying drawings.